The mechanism of long-range exciton diffusion in a nematically organized porphyrin layer.

نویسندگان

  • Annemarie Huijser
  • Tom J Savenije
  • Stefan C J Meskers
  • Martien J W Vermeulen
  • Laurens D A Siebbeles
چکیده

The exciton diffusion length in a nematically organized meso-tetra(4-n-butylphenyl)porphyrin (TnBuPP) layer was found to exceed 40 nm at a temperature of 90 K and to be equal to 22 +/- 3 nm at 300 K. The exciton diffusion coefficient decreases from > or = 3.1 x 10(-6) m(2)/s at 90 K to (2.5 +/- 0.5) x 10(-7) m(2)/s at 300 K. This thermal deactivation is attributed to exciton motion via a band mechanism. The motion of an exciton is not limited by polaronic effects; that is, the deformation of the atomic lattice around the exciton. The absence of polaronic self-trapping implies that the exciton diffusion coefficient can be enhanced by improvement of structural order and rigidity of the material.

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عنوان ژورنال:
  • Journal of the American Chemical Society

دوره 130 37  شماره 

صفحات  -

تاریخ انتشار 2008